Metal testing machine



" Nov. v16, 1937. f1-,1. NASS ET AL' "2,099,216

y y METAL TESTING ,MACHINE v Filed May 4, 1934 j, Wr

,. lill f INVENTORS y ATTORNEYS ParenteaNv. 16, 1937 f UNITED; STATES PATEN'roFFIcE Frederick ll. Nass and Ralph Campbell, Detroit, Mich.` z

Application Maya, `1934, serial No. 723.954

6 CliUlSr'WiCl. 265-12) Fig. 4 is a cross section taken lon the line The present Vinvention pertains to a novel device for testing the hardnessfof metal and relates more particularly 4to that .class vof testing machine wherein a test ball isv caused to penetrate the structure of a sample by building up high pressure thereon andthe hardness of the metal isjdetermined by the, amount of 'movementof l.the ball for a given pressure.l v

The primary object'of the present invention is to v,provide means for measuring the amount of movement of atest ball when a given pressure is applied thereon. It functions asa `comparative measuring device inasmuch as a sample of known hardness is first testedwith a: given pressure and the amount of movement is recorded ormarked on an indicator. Samples of metal of unknown hardness are then testedbyy subjecting them to the sameamount of pressure andsthe indicator compares the amount of movement Vofjthe test ball relative to the unknown Asample with vthe amount of movement relative tothe known sample and it is thus determine'clwhether or'not the hardnessof `the unknown sample is ywithin `the i manufacturers tolerance range.`

r Another object of the present invention is to provide a measuring attachment "formetal .testing. machines of the type wherein means are provided for building up pressure yuna test `ballto cause it toe/penetrate into the. inner structure of y a sample i of, metal; such measuring attachment being vconstructedkand arranged so that the accuracy of its function Iis not impaired by strains in the pressure meansor its support resultingv from the high pressure necessary ytocause themovef ment of the-ball.` To this end the measuring attachment constructedandy mounted entirely separate `from the pressure means and the frame which supports the pressure `means so thatwhen `the pressure means or frame become strained or slightly distorted or flexed-as arresult of the extremely `high ypressure on the test ball the'1accuracy of Ithe .reading 'provided by the'` present measuring device is in notway inuenced thereby.

. Withf the above andlotherV ends inv `view the in-f ventionconsists in matters hereinafter set .forth and more .particularly pointed out""in'thel apfpended claimareference being had `to the lfaccompan'ying drawing, in 'which 'i f i Figure f1 is a side elevation ofthe present vdevice applied to a testing machine, part of `the latter'being shown in cross section;

Fig. 2 is a front elevation; r

Fig. 3 .is a fragmentary central vertical cross section; f

ofFig.3; mh .Y 5 isan elevation of a detail, and j h Fig. 6 is a plan of a detail. s 1

Like characters of reference. are employed throughout to designate corresponding parts,`

Received on the 4post I is a jarnb nut 2 having a vflange 3 'by means of which it may bemanually rotated. Thisconstruction obviously constitutes va vertically adjustable work support of ajty'pe which is well known inthe art and which forms no part of the invention 'to be described."

Theupper' part of the kframe I is formed with a cylindrical bore 1havi`ng 'a shoulder-8.` A body 9 rests upon the shoulder 8 and is thus disposed partly in the bore 1 and partly out.` 1 `In the body 9y is formed a liquid reservoir I0, disposedinear vvthe upper end, and inthe bottomend is formed a cylindrical chamber I I. A hand pump I2 has its intake port I3l disposed within `the reservoir I0 and itsoutlet port lf3 enteringthe cylindrical chamber IIf. Thezin'letfand outlet 'ports rl3and I3 respectively 'are provided, as indicated; with check valves in the manner` well known` inthe vart and therefore not vshown in detail' here.

Aport I 4 is formedin thebody 9 to provide a means of direct communication between the chamber I I and the reservoir I ll and iscontrolled by asmanualvvalve I5.. An adjustablepressure regulating valve I5 is also providedtocontrol the port I4 for a purpose whichwill hereinafter ap pear. Siidabiy supported in thecylindrical'chamjdesired setting for the invention to be described.

The Afunction of the above described device is to movethe plunger lidownwardly and this is accomplished byoperating the pump lz'manually to force iiuidunder pressure from the reservoir r:sus

II) into the chamber II above the plunger. When the fluid pressure reaches a predetermined point the valve I5 functions to prevent its exceeding that point. It is obvious that this construction is merely shown by way of example and that the invention is applicable to any structure wherein a movable member is equipped with means for building up a predetermined pressure thereon.

'I'he novel measuring device includes an arm I8 which is shown in detail in Fig. 6, one end of the arm being provided with frictional clamping means I9 for adjustably securing it on a vertical post 28. It will be observed that the post 20 is entirely separate from the frame member I although it may be supported on the same base. 'I'he arm I8 has a bore 2| formed with an inwardly directed flange 22, the bore 2| being located directly beneath the bore 1 due to the irregularity in the shape of the arm as more clearly shown in Fig. 6. Loosely received in the bore 2| is a sleeve 23 having spaced peripheral flanges 24 adjacent to the upper end thereof and forming a circumferential groove. A pin 25 is'mounted in the arm I8 and 'its end projects into the groove formed by the ilanges 24, it being noted that the anges 24 are spaced apart a distance permitting a limited amount of longitudinal movement of the sleeve 23.Y A compressed vcoil spring 24' of comparatively light construction is sleeved around the sleeve 23 and has its opposite ends engaging the flange 22 and the lower flange 24 respectively. Pivotally mounted in the arm I8 is a lever 26 having its end 21 projecting into the groove formed by the flanges 24. 'I'he opposite end 28 engages a movable member 29 carrying a rack 30 meshing with a gear 3| on a shaft 32 carrying an vindicator needle 33 in the indicator housing .34, the needle cooperating with an indicia bearingvplate 35. A spring 36 normally urges the movable member 29 downwardly to maintain constant contact between the part 29 and theend 28 ofthe lever andthis contact tends to rock the lever 26 so as to maintain the end 21 in contact with the upper of the flanges 24. l

' Slidably received in the sleeve 23 is a cylindrical body 36 shown in detail in Fig. 5. The cylindrical body 36 is provided with machined bearing portions 31 adjacent to both its upper and lower ends which fit snugly in the sleeve 23 and is furthermore pierced with a substantially U-shaped saw cut in a manner to form a exible finger 38. A tubular member 39 is slidably received in the cylindrical body 36 and has an angular solid part 48 suitable for receiving a wrench so that the screwthreaded stem 4I formed integral thereon may be tightened in a screwthreaded bore 42 formed in the lower extremltyof the plunger I6. The tubular member 39 is formed with a slot 39 disposed in line radially with the flexible flnger'38- A head 43 has a hardened ball 44 supported thereon by a retainer 45, the head having an upwardly'extending hollow stem 46 slidably received in the tubular member 39. Abolt 41 has one end engaging the portion '40 and its other end received in a' screwthreaded bore 48 in the head 43 and serves as an adjustable means for tying the head 43 tothe tubular member 39. A comparatively heavy coiled spring 49 is interposed Finally the stem 46 is formed with acam shaped Vnotch 50 and a ball 5| is received in the slot 39 and has a portion thereof extending into the notch 50.

Prior to operation the bolt 41 is adjusted so that a clearance is maintained, as a result of pressure of spring 49, between the head 43 and the lower endof tubular member 39, and also between the upper end of the hollow stem 46 and the solid portion 40 of the tubular member 39. The sample piece of metal 6 is then placed on the work table 5 and the latter is elevated through operation of the sleeve 2 and screw post 4 until the work 6 is brought into contact with the test ball 44 in the manner shown in Fig. l. The device is then in readiness for testing the hardness of the sample 6.

I'he pump I2 is then operated to build up iluid pressure in the chamber II and the plunger I6 is caused to move downwardly. The tubular member 39 is carried downwardly with the plunger I6 and at the same time the stem 46 on the head 43 is held against movementr by engagement of the ball 44 with the sample 6. Therefore a relative `movement takesplace between the stem 46 and the tubular member 39 andthe clearance between the head 43 and tubular member 39 is thus'taken up by compressing the coiled spring 49. Simultaneous with the taking up of the clearance the ball 5| is carried downwardly by the tubular member 39 and engages the cam notch 50 whichthrusts it outwardly into engagement with the flexible finger 38. The vball 5I `causes the finger 38 to be flexed outwardly so that it frictionally engages the sleeve 23 and in this manner the sleeve 23 is connected to the head 43 to move therewith. 'I'he spring 49 is of suilicient strength that when it is compressed it exerts suicient thrust on the ball 44 to cause it to make good contact with the metal and therefore when the sleeve 23 becomes connected to the head 43 in the manner above described there is Asufllcient pressure being exerted by the spring 49 Lto take up all possiblelosses of motion so that when additional pressure is placed on the 'ball it will immediately begin to penetrate the structure of the sample. At this timethe pump` I2 is again operated and the parts move downwardly as the ball 44 is forced into the sample 6 and with the parts moves the sleeve 23. The flanges 24 cause the lever 26 to rock to move the rack 38 upwardly,rotate the gear 3|, and move the indicator needle 33. Theoperatlon ofl the pump I2 is continued until the pressure -valve I5' operates at which Ltime the maximum pressure has been reached and the amount of movement of the ball as a result of this pressure is noted. After the test is thus made the valve I5 is manually opened to permit the fluid to discharge from the chamber II into the reservoir-I0.

The above operation determines the amount of movement of the test ball 44 as a result of a given pressure and if the hardness of the sample is known other samples of unknown vhardness may be compared therewith by similar testing operations and by comparing the movement reading with the reading relative tothe sample of known hardness. It is obvious `that by testing several samples of different known hardness that a depth table may be provided which will obviate the necessity of testing different samples when the device is in use. l

It is obvious that the amount of pressurenecessary to cause the test ball 44 to function is very high and that a terrific stress is placedV on the G frame I as a result of the manner in which the two ends thereof tend to spread. Even if comme inaccurate `because of the manner 'I 4in `which measuring apparatus l`is entirely separate from pressure .means :as far as ,stresses concerned. it observed the measuring device is loosely interposed between the pressure mdium :and the vvork .and that it begins to. function :at the time :the test ball begins to enter the .structure of the sample.

Although :a speciiic embodiment of the present invention has been illustrated :and :described fit will be understood that various changes may abe made the scope of the :appended claims without departing from the spirit of the invention, and such changes are contemplated.

what we `claim yis:-

1. In a device o! the character described, a

plurality of relatively nesting parts, a 4test hall carried by one oi' said parts, an indicator connected to the other of said parts, frictonal means for connecting said `parts through relative movement therebetween, and pressure means for moving one of said parts.4

2. In a machine foi-,testing the hardness of metal, a test element holder having ya tubular part, a means for applying pressure to said holder also having a tubular part, said tubular parts being connected together in telescoped relationship by means positively restricting relative telescoping movement thereof, a spring .interposed between said holder and said pressure means and normally holding them extended, an indicator, an indicator actuating element, `and clutch means actuated byrelative movement of said telescoped `parts for connecting one of said parts with said indicator actuating element when pressure is applied thereto sumcient to compress said spring.

3. In a machine for testing the hardness of metal, a supporting frame having an indicator thereon, an indicator actuating element movably supported in said frame, a test. ball holder, a pressure apparatus, relatively telescoping parts interposed between said holder and said apparatus, yieldable means opposing telescopic movement of said parts, said yieldable means being adapted to be compressed when a predetermined back pressure is exerted against said ball holder, and a clutch device actuated by telescopic movement of said parts for connecting said indicator 50 actuator with one of said parts.

4.1namachlnefortestingthehardness of metal, a supporting irsme having an indicator thereon, :an indicator actuating element movahly supported in said frame, :a test bali holder, a pressure apparatus, :relatively telescoping parts .interposed between said holder and said apparatus, yieldahle means opposing telescopic` move- ;ment of said' parts, f "d yeldahle means being adapted to be compressed lwhen a predetermined hack pressure is exerted against said ball holder, :and .a friction clutch actuated by movement of said for connecting one of said parts with .said indicator :actua-tor..

5. 1n a machine :for testing lthe hardness oi metaL a test ball `holder having a tubular portion, means for applying pressure to said holder and also a tubular portion, the iirst named ltubular portion being received in the second named and having a cam surface coinciding with an opening in the second named tubular portion, a sleeve surrounding said second named portion and having` a flexible iinger aligned with said opening, a hall in said opening, means connecting said holder and first named means whereby a predetermined relative movement yis permitted therebetween, an indicator and an indicator actuating element adapted to be engaged by said iiexible iinger when relative movement between said tubular portions causes said cam to project said ball to flex said flexible iinger."

6. In a machine for testing the hardness of metal, a test ball holder having a tubular portion, means for applying pressure to said holder and also having a tubular portion, the ilrst named tubular portion being received in the second named and having a cam surface coinciding with an opening in the second named tubular portion,

a sleeve surrounding said second named tubular portion and having a flexible finger aligned with said opening, a ball in said opening, means connecting said holder and rst named means whereby a predetermined relative movement is permitted therebetween, means yieldably opposing relative movement between said tubular portions, an indicator, and an indicator actuating element adapted to be engaged by said flexible ilnger when relative movement between said tubular portions causes said cam to project said ball to ilex said nexible iinger. y

FREDERICK H. NABS.

RALPH CAMPBELL. 

